Canine ringworm caused by Trichophyton mentagrophytes - detection by SYBR-Green real-time PCR

Background: Dermatophytes, fungi of universal distribution, invade semi or fully keratinized structures, such as skin, fur/ hair and nails. The various species of dermatophytes are classified into three genera anamorphic: Microsporum, Trichophyton and Epidermophyton. The genus Epidermophyton includes only E. floccosum, that rarely affects animals. The main species responsible for the disease in dogs and cats are Microsporum canis, M. gypseum and Trichophyton mentagrophytes, which were characterized through conventional mycological methodology (microscopic examination with KOH and culture). Molecular methodologies, such as real-time PCR, can contribute to a rapid laboratory diagnosis, helping clinicians to initiate an early antifungal treatment. This case report describes a case of canine dermatophytosis due to Trichophyton mentagrophytes detected from a clinical sample by SYBR-Green real-time PCR. Case: A 8-year-old dog, rescued from the street, was referred to a private veterinary clinic in the city of Canoas, RS, Brazil, presenting generalized lymphadenomegaly, crusted lesions all over the body, generalized alopecia, signs of excoriation and epistaxis. Initially, were administered prednisone [1 mg/kg every 48 h, BID] and cephalexin [30 mg/kg, BID]. Weekly baths with benzoyl peroxide were also given. The therapy was not clinically successful. Wood's Lamp Test was negative. As a differential diagnosis, PCR for detection of Leishmania was negative. Complete blood count and serum biochemical assay were also performed. For mycological diagnosis, hair specimen was clarified and examined microscopically using 10% potassium hydroxide (KOH) for the visualization of chains of arthroconidia (ectothrix invasion of hair). The infected hair was plated onto MycoselTM Agar, incubated at 28°C for 15 days. Microscopy of hyphae/ conidia and macroscopic colony characteristics (colors and texture) were conducted for the differentiation of the species within the genus Microsporum and Trichophyton. In addition, real-time PCR was applied for direct analysis of the fungal DNA obtained from the hair sample. Microscopic examination was negative. The dermatophyte present in the hair sample was confirmed as Trichophyton mentagrophytes by culture and qPCR (melting-point analysis). The patient was treated with systemic itraconazole [10 mg/ kg SID - 90 days]. Twice-weekly application of 2.5 % miconazole and 2% chlorhexidine shampoo until complete cure. Discussion: Dermatophytosis is often listed as self-limiting infection; however, animal dermatophytosis can spread between pets, as well as a zoonotic transmission to humans. The literature on dermatophytosis indicates that Microsporum canis is the predominant etiological agent, followed by M. gypseum. Trichophyon mentagrophytes that appear in a lower percentage of isolation. The culture of hair, even with specific medium containing chloramphenicol and cyclohexamide, may present contaminating fungi, not related to dermatophytosis, which can inhibit or override the growth of dermatophytes. The use of real-time PCR provided a faster and specific diagnosis of dermatophytosis when compared to the conventional mycological methodology for detection and identification of T. mentagrophytes, which takes around 10 to 15 days for culture. It is possible to use this technique as an alternative diagnosis for dermatophytes associated to clinical hair samples of dogs.

Ocorrência de dermatófitos em tegumento de bovinos e ovinos hígidos / Occurrence of dermatophytes in healthy cattle and sheep tegument / Ocurrencia de dermatofitos en tegumento de bovinos y ovinos hígidos

O objetivo desta pesquisa foi verificar a prevalência de dermatófitos em tegumento de bovinos e ovinos hígidos e a sua capacidade de transmissão e desenvolvimento da doença. Para isso, foram coletadas amostras de pelo e descamações de 90 bovinos e 90 ovinos hígidos. Essas amostras foram semeadas em meio DTM e ágar Sabouraud Dextrose enriquecido com extrato de levedura, tiamina, antibióticos (estreptomicina e cloranfenicol) e suplementado de cicloheximida, sendo essas incubadas a 35 oC por 10 dias. As culturas positivas foram avaliadas macro e microscopicamente e, os fungos foram identificados por métodos bioquímicos. Verificou-se que as espécies isoladas com maior frequência, nos bovinos, foram T. mentagrophytes e M. gypseum. Nos ovinos, foi constatada maior ocorrência do agente T. verrucosum, seguido por T. mentagrophytes e M. gypseum. Houve também isolamento de M. canis, porém, em um número reduzido de amostras. Assim, concluiu-se que o tegumento de bovinos e de ovinos hígidos apresentou incidência elevada de dermatófitos de diferentes espécies, em amostras coletadas durante o período chuvoso do ano. Por isso, em animais jovens ou naqueles submetidos a elevados níveis de estresse e, consequente queda da resposta imunológica, o risco de desenvolvimento da dermatofitose e da transmissão dos dermatófitos neste período são eminentes.(AU)

The purpose of this study was to determine the prevalence of dermatophytes in healthy cattle and sheep teguments, and their ability to transmit and develop diseases. Samples of fur and flaking from 90 healthy cattle and 90 healthy sheep were collected. These samples were plated on DTM medium and Sabouraud Dextrose agar supplemented with yeast extract, thiamine, antibiotics (streptomycin and chloramphenicol) enhanced with cycloheximide. They were then incubated at 35 °C for 10 days. Positive cultures were macroscopically and microscopically evaluated, and fungi were identified by biochemical methods. It was found that the most frequent species isolated in cattle were T. mentagrophytes and M. gypseum. In sheep, a higher occurrence of the agent T. verrucosum could be observed, followed by T. mentagrophytes and M. gypseum. There was also the isolation of M. canis, but in a small number of samples. Thus, it could be concluded that the tegument of healthy cattle and sheep showed high incidence of dermatophytes from different species in samples collected during the rainy season of the year. Therefore, in young animals, in those subjected to high levels of stress and consequent drop in immune response, there is eminent risk of developing dermatophytosis and transmission of dermatophytes in this period.(AU)

El objetivo de esta investigación ha sido verificar la prevalencia de dermatofitos en tegumento de bovinos y ovinos hígidos y su capacidad de transmisión y desarrollo de la enfermedad. Para ello, se recolectó muestras de pelo y descamaciones de 90 bovinos y 90 ovinos hígidos. Esas muestras fueron sembradas en medio DTM y agar Sabouraud Dextrosis enriquecida con extracto de levadura, tiamina, antibióticos (estreptomicina y cloranfenicol) y suplementado de cicloheximida, siendo esas incubadas a 35ºC durante 10 días. Los cultivos positivos fueron evaluados macro y microscópicamente y los hongos fueron identificados por métodos bioquímicos. Se verificó que las especies aisladas con mayor frecuencia, en los bovinos, fueron T. mentagrophytes y M. gypseum. En los ovinos, se constató mayor ocurrencia del agente T. verrucosum, seguido por T. mentagrophytes y M. gypseum. También hubo aislamiento de M. canis, sin embargo, en un número reducido de muestras. Así, se concluyó que el tegumento de bovinos y de ovinos hígidos presentó una elevada incidencia de dermatofitos de diferentes especies, en muestras recogidas durante el período lluvioso del año. Por lo tanto, en animales jóvenes o en aquellos sometidos a altos niveles de estrés y, consecuente caída de la respuesta inmunológica, el riesgo de desarrollo de la dermatofitosis y de la transmisión de los dermatofitos en este período son eminentes.(AU)

Ocorrência de dermatófitos em tegumento de bovinos e ovinos hígidos / Occurrence of dermatophytes in healthy cattle and sheep tegument / Ocurrencia de dermatofitos en tegumento de bovinos y ovinos hígidos

O objetivo desta pesquisa foi verificar a prevalência de dermatófitos em tegumento de bovinos e ovinos hígidos e a sua capacidade de transmissão e desenvolvimento da doença. Para isso, foram coletadas amostras de pelo e descamações de 90 bovinos e 90 ovinos hígidos. Essas amostras foram semeadas em meio DTM e ágar Sabouraud Dextrose enriquecido com extrato de levedura, tiamina, antibióticos (estreptomicina e cloranfenicol) e suplementado de cicloheximida, sendo essas incubadas a 35 oC por 10 dias. As culturas positivas foram avaliadas macro e microscopicamente e, os fungos foram identificados por métodos bioquímicos. Verificou-se que as espécies isoladas com maior frequência, nos bovinos, foram T. mentagrophytes e M. gypseum. Nos ovinos, foi constatada maior ocorrência do agente T. verrucosum, seguido por T. mentagrophytes e M. gypseum. Houve também isolamento de M. canis, porém, em um número reduzido de amostras. Assim, concluiu-se que o tegumento de bovinos e de ovinos hígidos apresentou incidência elevada de dermatófitos de diferentes espécies, em amostras coletadas durante o período chuvoso do ano. Por isso, em animais jovens ou naqueles submetidos a elevados níveis de estresse e, consequente queda da resposta imunológica, o risco de desenvolvimento da dermatofitose e da transmissão dos dermatófitos neste período são eminentes.(AU)

The purpose of this study was to determine the prevalence of dermatophytes in healthy cattle and sheep teguments, and their ability to transmit and develop diseases. Samples of fur and flaking from 90 healthy cattle and 90 healthy sheep were collected. These samples were plated on DTM medium and Sabouraud Dextrose agar supplemented with yeast extract, thiamine, antibiotics (streptomycin and chloramphenicol) enhanced with cycloheximide. They were then incubated at 35 °C for 10 days. Positive cultures were macroscopically and microscopically evaluated, and fungi were identified by biochemical methods. It was found that the most frequent species isolated in cattle were T. mentagrophytes and M. gypseum. In sheep, a higher occurrence of the agent T. verrucosum could be observed, followed by T. mentagrophytes and M. gypseum. There was also the isolation of M. canis, but in a small number of samples. Thus, it could be concluded that the tegument of healthy cattle and sheep showed high incidence of dermatophytes from different species in samples collected during the rainy season of the year. Therefore, in young animals, in those subjected to high levels of stress and consequent drop in immune response, there is eminent risk of developing dermatophytosis and transmission of dermatophytes in this period.(AU)

El objetivo de esta investigación ha sido verificar la prevalencia de dermatofitos en tegumento de bovinos y ovinos hígidos y su capacidad de transmisión y desarrollo de la enfermedad. Para ello, se recolectó muestras de pelo y descamaciones de 90 bovinos y 90 ovinos hígidos. Esas muestras fueron sembradas en medio DTM y agar Sabouraud Dextrosis enriquecida con extracto de levadura, tiamina, antibióticos (estreptomicina y cloranfenicol) y suplementado de cicloheximida, siendo esas incubadas a 35ºC durante 10 días. Los cultivos positivos fueron evaluados macro y microscópicamente y los hongos fueron identificados por métodos bioquímicos. Se verificó que las especies aisladas con mayor frecuencia, en los bovinos, fueron T. mentagrophytes y M. gypseum. En los ovinos, se constató mayor ocurrencia del agente T. verrucosum, seguido por T. mentagrophytes y M. gypseum. También hubo aislamiento de M. canis, sin embargo, en un número reducido de muestras. Así, se concluyó que el tegumento de bovinos y de ovinos hígidos presentó una elevada incidencia de dermatofitos de diferentes especies, en muestras recogidas durante el período lluvioso del año. Por lo tanto, en animales jóvenes o en aquellos sometidos a altos niveles de estrés y, consecuente caída de la respuesta inmunológica, el riesgo de desarrollo de la dermatofitosis y de la transmisión de los dermatofitos en este período son eminentes.(AU)

Isolamento e perfil enzimático de cães e gatos com dermatofitose atendidos em hospitais veterinários do Recife, Pernambuco / Isolation and enzymatic profile of dogs and cats with dermatofitosis attended at veterinary hospitals in Recife, Pernambuco, Brazil

Os dermatófitos são fungos que podem causar infecções superficiais da pele, cabelo e unhas em humanos e animais. As espécies de dermatófitos mais frequentemente isoladas dos cães e gatos afetados por micoses são Microsporum gypseum e principalmente Microsporum canis. O papel crucial durante o processo de infecção é a produção de enzimas extracelulares essenciais para a invasão e estabelecimento do agente patogênico no tecido do hospedeiro. O objetivo deste trabalho foi isolar dermatófitos de cães e gatos e avaliar o perfil enzimático dos isolados obtidos. Amostras de pelos e escamas epidérmicas foram coletadas de cães e gatos em instalações veterinárias em Recife/PE, e os isolados foram identificados com base nas características macroscópicas e microscópicas. A análise qualitativa das enzimas urease, protease, lipase, colagenase e fosfolipase foi avaliada a partir dos dermatófitos isolados. Durante 10 meses, um total de 106 animais, que compreendeu de 99 cães e sete gatos com sinais clínicos, independentemente do sexo e raça foram avaliados. Apenas oito animais foram confirmados com dermatofitose, principalmente cães (n=7), sendo seis afetados por M. canis e um por M. gypseum, a raça mais afetada foi Yorkshire (n=3). No entanto, apenas um gato foi confirmado com M. canis. Não foi observada predisposição relacionada ao sexo quanto à ocorrência de dermatofitose nos cães e gatos avaliados. Os dermatófitos isolados apresentaram perfis semelhantes para as enzimas urease, lipase, protease, fosfolipase e colagenase, característica importante em infecções patogênicas. O diagnóstico clínico destas zoonoses com base na confirmação microbiológica e uma compreensão dos mecanismos subjacentes é de grande importância para o tratamento e prevenção de doenças fúngicas em animais.(AU)

Dermatophytes are fungi that can cause superficial infections of the skin, hair and nails in man and animals. The most frequent dermatophyte species isolated from dogs and cats are Microsporum gypseum, most notably Microsporum canis. The crucial role during the infection process is the production of extracellular enzymes essential for the invasion and establishment of the pathogen in the host tissue. The objective of this research was to isolate dermatophytes from dogs and cats and evaluate the enzymatic profile of the isolates obtained. Hair samples and epidermal scales were collected from dogs and cats in veterinary facilities in Recife-PE, and the isolates were identified based on macroscopic and microscopic characteristics. The qualitative analysis of the enzymes urease, protease, lipase, collagenase and phospholipase was evaluated from the isolated dermatophytes. During 10 months, a total of 106 animals, comprising of 99 dogs and seven cats with clinical signs, regardless of sex and race were evaluated. Only eight animals were confirmed with dermatophytosis, mostly dogs (n=7), being six affected by M. canis and one by M. gypseum, the race most affected was Yorkshire (n=3). However, only one cat was confirmed with M. canis. No sex-related predisposition was observed regarding the occurrence of dermatophytosis in dogs and cats evaluated. Isolated dermatophytes showed similar profiles for the enzymes urease, lipase, protease, phospholipase and collagenase, important characteristic for pathogenic infections. The diagnosis of this zoonosis based on microbiological confirmation and a better understanding of the underlying mechanisms is of great importance for the treatment and prevention of fungal diseases in animals.(AU)

Isolamento e perfil enzimático de cães e gatos com dermatofitose atendidos em hospitais veterinários do Recife, Pernambuco / Isolation and enzymatic profile of dogs and cats with dermatofitosis attended at veterinary hospitals in Recife, Pernambuco, Brazil

Os dermatófitos são fungos que podem causar infecções superficiais da pele, cabelo e unhas em humanos e animais. As espécies de dermatófitos mais frequentemente isoladas dos cães e gatos afetados por micoses são Microsporum gypseum e principalmente Microsporum canis. O papel crucial durante o processo de infecção é a produção de enzimas extracelulares essenciais para a invasão e estabelecimento do agente patogênico no tecido do hospedeiro. O objetivo deste trabalho foi isolar dermatófitos de cães e gatos e avaliar o perfil enzimático dos isolados obtidos. Amostras de pelos e escamas epidérmicas foram coletadas de cães e gatos em instalações veterinárias em Recife/PE, e os isolados foram identificados com base nas características macroscópicas e microscópicas. A análise qualitativa das enzimas urease, protease, lipase, colagenase e fosfolipase foi avaliada a partir dos dermatófitos isolados. Durante 10 meses, um total de 106 animais, que compreendeu de 99 cães e sete gatos com sinais clínicos, independentemente do sexo e raça foram avaliados. Apenas oito animais foram confirmados com dermatofitose, principalmente cães (n=7), sendo seis afetados por M. canis e um por M. gypseum, a raça mais afetada foi Yorkshire (n=3). No entanto, apenas um gato foi confirmado com M. canis. Não foi observada predisposição relacionada ao sexo quanto à ocorrência de dermatofitose nos cães e gatos avaliados. Os dermatófitos isolados apresentaram perfis semelhantes para as enzimas urease, lipase, protease, fosfolipase e colagenase, característica importante em infecções patogênicas. O diagnóstico clínico destas zoonoses com base na confirmação microbiológica e uma compreensão dos mecanismos subjacentes é de grande importância para o tratamento e prevenção de doenças fúngicas em animais.(AU)

Dermatophytes are fungi that can cause superficial infections of the skin, hair and nails in man and animals. The most frequent dermatophyte species isolated from dogs and cats are Microsporum gypseum, most notably Microsporum canis. The crucial role during the infection process is the production of extracellular enzymes essential for the invasion and establishment of the pathogen in the host tissue. The objective of this research was to isolate dermatophytes from dogs and cats and evaluate the enzymatic profile of the isolates obtained. Hair samples and epidermal scales were collected from dogs and cats in veterinary facilities in Recife-PE, and the isolates were identified based on macroscopic and microscopic characteristics. The qualitative analysis of the enzymes urease, protease, lipase, collagenase and phospholipase was evaluated from the isolated dermatophytes. During 10 months, a total of 106 animals, comprising of 99 dogs and seven cats with clinical signs, regardless of sex and race were evaluated. Only eight animals were confirmed with dermatophytosis, mostly dogs (n=7), being six affected by M. canis and one by M. gypseum, the race most affected was Yorkshire (n=3). However, only one cat was confirmed with M. canis. No sex-related predisposition was observed regarding the occurrence of dermatophytosis in dogs and cats evaluated. Isolated dermatophytes showed similar profiles for the enzymes urease, lipase, protease, phospholipase and collagenase, important characteristic for pathogenic infections. The diagnosis of this zoonosis based on microbiological confirmation and a better understanding of the underlying mechanisms is of great importance for the treatment and prevention of fungal diseases in animals.(AU)

Isolamento e perfil enzimático de cães e gatos com dermatofitose atendidos em hospitais veterinários do Recife, Pernambuco

ABSTRACT: Dermatophytes are fungi that can cause superficial infections of the skin, hair and nails in man and animals. The most frequent dermatophyte species isolated from dogs and cats are Microsporum gypseum, most notably Microsporum canis. The crucial role during the infection process is the production of extracellular enzymes essential for the invasion and establishment of the pathogen in the host tissue. The objective of this research was to isolate dermatophytes from dogs and cats and evaluate the enzymatic profile of the isolates obtained. Hair samples and epidermal scales were collected from dogs and cats in veterinary facilities in Recife-PE, and the isolates were identified based on macroscopic and microscopic characteristics. The qualitative analysis of the enzymes urease, protease, lipase, collagenase and phospholipase was evaluated from the isolated dermatophytes. During 10 months, a total of 106 animals, comprising of 99 dogs and seven cats with clinical signs, regardless of sex and race were evaluated. Only eight animals were confirmed with dermatophytosis, mostly dogs (n=7), being six affected by M. canis and one by M. gypseum, the race most affected was Yorkshire (n=3). However, only one cat was confirmed with M. canis. No sex-related predisposition was observed regarding the occurrence of dermatophytosis in dogs and cats evaluated. Isolated dermatophytes showed similar profiles for the enzymes urease, lipase, protease, phospholipase and collagenase, important characteristic for pathogenic infections. The diagnosis of this zoonosis based on microbiological confirmation and a better understanding of the underlying mechanisms is of great importance for the treatment and prevention of fungal diseases in animals.

RESUMO: Os dermatófitos são fungos que podem causar infecções superficiais da pele, cabelo e unhas em humanos e animais. As espécies de dermatófitos mais frequentemente isoladas dos cães e gatos afetados por micoses são Microsporum gypseum e principalmente Microsporum canis. O papel crucial durante o processo de infecção é a produção de enzimas extracelulares essenciais para a invasão e estabelecimento do agente patogênico no tecido do hospedeiro. O objetivo deste trabalho foi isolar dermatófitos de cães e gatos e avaliar o perfil enzimático dos isolados obtidos. Amostras de pelos e escamas epidérmicas foram coletadas de cães e gatos em instalações veterinárias em Recife/PE, e os isolados foram identificados com base nas características macroscópicas e microscópicas. A análise qualitativa das enzimas urease, protease, lipase, colagenase e fosfolipase foi avaliada a partir dos dermatófitos isolados. Durante 10 meses, um total de 106 animais, que compreendeu de 99 cães e sete gatos com sinais clínicos, independentemente do sexo e raça foram avaliados. Apenas oito animais foram confirmados com dermatofitose, principalmente cães (n=7), sendo seis afetados por M. canis e um por M. gypseum, a raça mais afetada foi Yorkshire (n=3). No entanto, apenas um gato foi confirmado com M. canis. Não foi observada predisposição relacionada ao sexo quanto à ocorrência de dermatofitose nos cães e gatos avaliados. Os dermatófitos isolados apresentaram perfis semelhantes para as enzimas urease, lipase, protease, fosfolipase e colagenase, característica importante em infecções patogênicas. O diagnóstico clínico destas zoonoses com base na confirmação microbiológica e uma compreensão dos mecanismos subjacentes é de grande importância para o tratamento e prevenção de doenças fúngicas em animais.

Zoonotic transmission of canine sporotrichosis in northeastern Brazil

Sporotrichosis is a subcutaneous mycosis, caused by the fungal complex Sporothrix schenckii, and composed of several species of the genus. Although diseased dogs show the minimal risk of infection to humans, such susceptibility is non-null and, therefore, should be considered. In the Northeast of Brazil, such mycosis has been reported in dogs but its role in local public health is still unknown. The objective of this study was to report the occurrence of canine sporotrichosis with transference capacity to humans, pointing a case in a Brazilian northeastern city. An 11-year-old male dachshund dog presenting skin lesions for two months. The dog was autochthonous to the city of Natal. The animal was referred for physical evaluation. Subcutaneous nodules were detected in the nasal and ventral-cervical regions. An incisional biopsy of the lesions was performed, subjecting the samples to histopathology. Itraconazole (10 mg/ kg, orally, every 24 hours) was prescribed. After a few days under physical evaluation, the guardian of the animal noticed alterations in the integument of her left upper limb. A clinical laboratory examination by a dermatologist detected sporotrichosis condition, being the animal caregiver submitted to a specialized therapy. The dermato-histopathology of the canine revealed the presence of Sporothrix spp., thus confirming the diagnosis of sporotrichosis. After the histopathological examination, itraconazole therapy was continued, achieving a complete lesion regression after 120 days. In dogs infected with the S. schenckii complex, transmission to humans should be considered regardless of the affected animal species, once sporotrichosis is an anthropozoonosis.

Dermatophytes in Cats without Dermatopathies in the Metropolitan Area of Florianópolis, Brazil

Background: Dermatophytes are infectious agents responsible for dermatophytosis, an important worldwide zoonosis. Cats are considered potential hosts and reservoir of these fungi, especially Microsporum canis. The prevalence in cats without dermatopathies varies according to the region, climate and animal husbandry. The aim of this study was to estimate the frequency of dermatophytes in cats without clinical signs of dermatopathy in the Metropolitan Area of Florianópolis, situated in the coast of Southern Brazil.Materials, Methods & Results: A total of 198 samples were obtained from cats without dermatopathies domiciled in the metropolitan area of Florianópolis. The collections were made through vigorous hair brushing throughout the body of the animal, using a sterile toothbrush. Mycological culture was performed onto Sabouraud Agar Chloramphenicol-Cyclohexamide (SCC), and incubated at 25-27C for 21-28 days. The diagnosis was based on the macro and micromorphological characteristics of the isolated dermatophyte. One hundred and ten samples (55.6%) were collected in veterinary clinics and 88 (44.4%) in multiple household cats (average 11). The frequency of dermatophytes corresponded to 3.0% (6/198). Only the genus Microsporum was observed with predominance of M. canis (66.7%), followed by M. gypseum (33.3%). Saprotrophic fungi were observed in 94.4% of the cultures and 5.6%

Zoonotic transmission of canine sporotrichosis in northeastern Brazil

Sporotrichosis is a subcutaneous mycosis, caused by the fungal complex Sporothrix schenckii, and composed of several species of the genus. Although diseased dogs show the minimal risk of infection to humans, such susceptibility is non-null and, therefore, should be considered. In the Northeast of Brazil, such mycosis has been reported in dogs but its role in local public health is still unknown. The objective of this study was to report the occurrence of canine sporotrichosis with transference capacity to humans, pointing a case in a Brazilian northeastern city. An 11-year-old male dachshund dog presenting skin lesions for two months. The dog was autochthonous to the city of Natal. The animal was referred for physical evaluation. Subcutaneous nodules were detected in the nasal and ventral-cervical regions. An incisional biopsy of the lesions was performed, subjecting the samples to histopathology. Itraconazole (10 mg/ kg, orally, every 24 hours) was prescribed. After a few days under physical evaluation, the guardian of the animal noticed alterations in the integument of her left upper limb. A clinical laboratory examination by a dermatologist detected sporotrichosis condition, being the animal caregiver submitted to a specialized therapy. The dermato-histopathology of the canine revealed the presence of Sporothrix spp., thus confirming the diagnosis of sporotrichosis. After the histopathological examination, itraconazole therapy was continued, achieving a complete lesion regression after 120 days. In dogs infected with the S. schenckii complex, transmission to humans should be considered regardless of the affected animal species, once sporotrichosis is an anthropozoonosis.(AU)

Dermatophytes in cats without dermatopathies in the Metropolitan Area of Florianópolis, Brazil / Dermatófitos em gatos sem dermatopatias na região metropolitana de Florianópolis, Brasil

Background: Dermatophytes are infectious agents responsible for dermatophytosis, an important worldwide zoonosis. Cats are considered potential hosts and reservoir of these fungi, especially Microsporum canis. The prevalence in cats without dermatopathies varies according to the region, climate and animal husbandry. The aim of this study was to estimate the frequency of dermatophytes in cats without clinical signs of dermatopathy in the Metropolitan Area of Florianópolis, situated in the coast of Southern Brazil. Materials, Methods & Results: A total of 198 samples were obtained from cats without dermatopathies domiciled in the metropolitan area of Florianópolis. The collections were made through vigorous hair brushing throughout the body of the animal, using a sterile toothbrush. Mycological culture was performed onto Sabouraud Agar Chloramphenicol-Cyclohexamide (SCC), and incubated at 25-27C for 21-28 days. The diagnosis was based on the macro and micromorphological characteristics of the isolated dermatophyte. One hundred and ten samples (55.6%) were collected in veterinary clinics and 88 (44.4%) in multiple household cats (average 11). The frequency of dermatophytes corresponded to 3.0% (6/198). Only the genus Microsporum was observed with predominance of M. canis (66.7%), followed by M. gypseum (33.3%). Saprotrophic fungi were observed in 94.4% of the cultures and [...]

Dermatophytes in cats without dermatopathies in the Metropolitan Area of Florianópolis, Brazil / Dermatófitos em gatos sem dermatopatias na região metropolitana de Florianópolis, Brasil

Background: Dermatophytes are infectious agents responsible for dermatophytosis, an important worldwide zoonosis. Cats are considered potential hosts and reservoir of these fungi, especially Microsporum canis. The prevalence in cats without dermatopathies varies according to the region, climate and animal husbandry. The aim of this study was to estimate the frequency of dermatophytes in cats without clinical signs of dermatopathy in the Metropolitan Area of Florianópolis, situated in the coast of Southern Brazil. Materials, Methods & Results: A total of 198 samples were obtained from cats without dermatopathies domiciled in the metropolitan area of Florianópolis. The collections were made through vigorous hair brushing throughout the body of the animal, using a sterile toothbrush. Mycological culture was performed onto Sabouraud Agar Chloramphenicol-Cyclohexamide (SCC), and incubated at 25-27C for 21-28 days. The diagnosis was based on the macro and micromorphological characteristics of the isolated dermatophyte. One hundred and ten samples (55.6%) were collected in veterinary clinics and 88 (44.4%) in multiple household cats (average 11). The frequency of dermatophytes corresponded to 3.0% (6/198). Only the genus Microsporum was observed with predominance of M. canis (66.7%), followed by M. gypseum (33.3%). Saprotrophic fungi were observed in 94.4% of the cultures and [...](AU)

Anti-fungal potential of ozone against some dermatophytes

Dermatophytes are classified in three genera, Epidermophyton, Microsporum and Trichophyton. They have the capacity to invade keratinized tissue to produce a cutaneous infection known as dermatophytoses. This investigation was performed to study the effect of gaseous ozone and ozonized oil on three specific properties of six different dermatophytes. These properties included sporulation, mycelia leakage of sugar and nutrients and the activity of their hydrolytic enzymes. Generally, ozonized oil was found to be more efficacious than gaseous ozone. Microsporum gypseum and Microsporum canis were the most susceptible, while Trichophyton interdigitale and T. mentagrophytes were relatively resistant. The study revealed a steady decline in spore production of M. gypseum and M. canis on application of ozonated oil. An increase in leakage of electrolytes and sugar was noticed after treatment with ozonized oil in the case of M. gypseum, M. canis, T. interdigitale, T. mentagrophytes and T. rubrum. The results also revealed loss in urease, amylase, alkaline phosphatase, lipase and keratinase enzyme producing capacity of the investigated fungi.(AU)

Isolation of dermatophytes from the hair coat of healthy Persian cats without skin lesions from commercial catteries located in São Paulo metropolitan area, Brazil

Background: The study of the epidemiological chain of dermatophytosis, particularly those related to zoophilic fungi, is extremely important because of its frequent occurrence, the high infectivity of the agent, and its anthropozoonotic character. In all latitudes, asymptomatic cats are considered the main reservoirs and sources of dermatophyte infection. The study aimed to characterize the frequency of dermatophyte infection and the potential risk of microsporic infection to the owners and to possible buyers of apparently healthy Persian cats from commercial catteries of São Paulo, Brazil. Materials, Methods & Results: Fur samples were obtained from 61 clinically healthy Persian cats, which were devoid of typical cutaneous lesions and had negative results in Woods lamp examination. The average age of the cats was 37.7 months; 18 (29.5%) of them were males and 43 (70.5%) were females. The cats were from commercial catteries located in the metropolitan region of São Paulo state capital. Samples were obtained using the technique of Mariat & Adam using a square (25 cm2 ) of sterile carpet rubbed across the surface of the hair-coat and skin. People who had close contact with the animals were asked whether they had had typical ringworm lesions in the recent past or at the time of sample collection. The material collected was pressed onto Petri dishes containing agar [...](AU)

Isolation of dermatophytes from the hair coat of healthy Persian cats without skin lesions from commercial catteries located in São Paulo metropolitan area, Brazil

Background: The study of the epidemiological chain of dermatophytosis, particularly those related to zoophilic fungi, is extremely important because of its frequent occurrence, the high infectivity of the agent, and its anthropozoonotic character. In all latitudes, asymptomatic cats are considered the main reservoirs and sources of dermatophyte infection. The study aimed to characterize the frequency of dermatophyte infection and the potential risk of microsporic infection to the owners and to possible buyers of apparently healthy Persian cats from commercial catteries of São Paulo, Brazil. Materials, Methods & Results: Fur samples were obtained from 61 clinically healthy Persian cats, which were devoid of typical cutaneous lesions and had negative results in Woods lamp examination. The average age of the cats was 37.7 months; 18 (29.5%) of them were males and 43 (70.5%) were females. The cats were from commercial catteries located in the metropolitan region of São Paulo state capital. Samples were obtained using the technique of Mariat & Adam using a square (25 cm2 ) of sterile carpet rubbed across the surface of the hair-coat and skin. People who had close contact with the animals were asked whether they had had typical ringworm lesions in the recent past or at the time of sample collection. The material collected was pressed onto Petri dishes containing agar [...]

Fatores de virulência de Nannizzia gypsea isoladas de solo de parques do município de São Paulo

Por sua característica zoonótica, a dermatofitose tem grande importância para a saúde pública. Particularmente, os dermatófitos geofílicos são insuficientemente estudados por serem considerados estritamente oportunistas; entretanto, Nannizzia gypsea (sin. Microsporum gypseum), que é geofílica, tem sido isolada por todo o mundo causando infecções no homem e animais, confirmando o potencial patogênico que os fungos geofílicos apresentam. O sucesso no estabelecimento da infecção pelos dermatófitos depende de varias proteínas e enzimas fúngicas, que são a chave na invasão e utilização do estrato córneo do hospedeiro; portanto, o estudo dos fatores de virulência envolvidos na patogenicidade desses fungos auxiliará na compreensão da epidemiologia das dermatofitoses. Objetivo: O objetivo do presente estudo foi pesquisar a secreção de hemolisinas e das enzimas proteinase, fosfolipase, lipase e gelatinase em cepas de N. gypsea. Métodos: Foram testadas 21 cepas de N. gypsea isoladas do solo de 21 parques do município de São Paulo pela técnica de Vanbreuseghem. A produção das enzimas fosfolipase, proteinase e lipase foi verificada empregando-se placas de Petri com meio sólido contendo o respectivo substrato a ser degradado, respectivamente, gema de ovo, albumina sérica bovina e Tween 20. O teste foi considerado positivo quando ocorreu uma zona clara de degradação ao redor da colônia. Para a verificação da produção da enzima gelatinase foi empregado meio contendo gelatina, o qual foi distribuído em tubos; a semeadura ocorreu em picada e antes da leitura final, os tubos foram refrigerados a 4° C por 30 minutos. O teste foi considerado positivo quando houve liquefação do meio. Na prova da produção de hemolisinas empregou-se base de ágar sangue suplementada com 5% de sangue de carneiro desfibrinado; nesta prova, após a leitura de 14 dias, as placas foram incubadas a 32° C. Em cada um dos testes, após a semeadura, as placas foram incubadas por 14 dias a 25° C, realizando-se leituras aos 5, 7, 10 e 14 dias. Resultados: Todas as 21 cepas de N. gypsea produziram fosfolipase aos 14 dias, gelatinase, a partir de 10 dias, proteinase e lipase, a partir de 7 dias de incubação. Em relação à fosofolipase, a maioria das reações foi fortemente positiva para a produção da enzima. Aos 14 dias a 32° C, se verificou hemólise em 81,0% (17/21) das cepas, sendo 82,4% (14/17) de -hemólise (hemólises parciais) e 17,6% (3/17) de -hemólise (hemólise total). Todas as cepas de N. gypsea testadas produziram enzimas e/ou hemolisinas, consideradas fatores de virulência, revelando seu potencial de patogenicidade. Os intervalos de leitura ideais para a produção das enzimas fosfolipase, proteinase, lipase e gelatinase foram, respectivamente, 14, 7, 7 e 10 dias; em relação à atividade hemolítica sugere-se 14 dias com temperatura de 32° C. Conclusão: A presença de N. gypsea, com a produção de fatores de virulência em solos de parques do município de São Paulo, pode representar potencial risco de infecção aos humanos e animais que usufruem desses espaços dedicados ao lazer.

Dermatophytosis is of significant importance for public health because of its zoonotic characteristic. In particular, geophilic dermatophytes have been insufficiently studied because they are considered strictly opportunistic. However, cases of infections due to Nannizzia gypsea (syn. Microsporum gypseum), a geophilic dermatophyte, in both humans and animals have been found globally, confirming the pathogenic potential of geophilic fungi. Dermatophytoses caused by these fungi is attributed to several proteins and enzymes produced by them and also the use of the hosts stratum corneum by the fungi. Therefore, the study of virulence factors of these fungi will be helpful in understanding the epidemiology of dermatophytoses. The aim of this study was to investigate the secretion of hemolysins, proteinase, phospholipase, lipase, and gelatinase enzymes by N. gypsea strains. Twenty-one strains of N. gypsea isolated using the Vanbreuseghem technique from the soil samples of 21 parks in São Paulo, Brazil, were tested. The production of phospholipase, proteinase, and lipase was verified by culturing these strains in Petri dishes containing a solid culture medium. This medium contained the respective substrate for degradation such as egg yolk, bovine serum albumin, and Tween 20. The test was considered positive when there was a clear area of degradation around the colony. To check the production of gelatinase, a medium containing gelatin was used that was distributed in tubes and punctiform inoculation was performed. Before the final reading, the tubes were refrigerated at 4° C for 30 min. The test was considered positive when there was a liquefaction of the medium. In the hemolysin production test, blood agar base supplemented with 5% defibrinated sheep blood was used. In this test, after reading for 14 days, the plates were incubated at 32° C. In each of these tests, after inoculation, the plates were incubated for 14 days at 25° C, with readings taken at 5, 7, 10, and 14 days. All the 21 strains of N. gypsea produced phospholipase at 14 days, gelatinase from 10 days, and proteinase and lipase from 7 days of incubation. Most of the reactions were strongly positive for the production of phospholipase. At 14 days at 32° C, hemolysis was observed in 81.0% (17/21) of the strains, with -hemolysis (partial hemolysis) in 82.4% (14/17) of the strains and -hemolysis (complete hemolysis) in 17.6% (3/17) of the strains. One of the strains produced both - and -hemolysis. All the strains of N. gypsea produced enzymes and/or hemolysins, which are considered virulence factors, thus revealing their pathogenic potential. The ideal reading intervals for detecting the production of phospholipase, proteinase, lipase, and gelatinase were 14, 7, 7, and 10 days respectively. For detecting hemolytic activity, 14 days at a temperature of 32° C is recommended. The presence of virulent strains of N. gypsea in the soils of parks in São Paulo may represent a potential risk of infection to humans and animals that enjoy these spaces for leisure.

Avaliação do microbioma cutâneo de gatos com dermatofitose pela técnica de sequenciamento de alto rendimento e caracterização de proteínas imunodominantes do Microsporum canis para o sorodiagnóstico da dermatofitose felina

A dermatofitose e uma doenca fungica comumente vista no atendimento ambulatorial de felinos. A sua importancia clinica e epidemiologica reside no fato de ser uma dermatopatia cosmopolita, infecciosa, contagiosa e zoonotica. Atualmente, o cultivo fungico e a principal ferramenta de diagnostico utilizada, porem a sua morosidade na emissao do resultado indica a necessidade do desenvolvimento de novas estrategias de diagnostico. A aplicacao de tecnologias de imunodiagnostico, bem como tecnologias de sequenciamento da microbiota, tem um grande potencial para contribuir na identificacao e desenvolvimento de novos alvos diagnosticos. O objetivo desse estudo foi identificar e caracterizar as proteinas imunodominantes do Microsporum canis para aplicabilidade no sorodiagnostico da dermatofitose felina. Alem disso, objetivou-se avaliar a composicao e a diversidade das microbiotas fungica e bacteriana de gatos com dermatofitose, gatos assintomaticos (carreadores de M. canis) e gatos higidos. Para os ensaios de caracterizacao das proteinas de M. canis, foram colhidas amostras cutaneas e de sangue de 70 felinos: sintomaticos (n= 20), assintomaticos (n= 20), negativos (n = 20) e negativos heterologos (n= 10). As amostras cutaneas foram submetidas a cultivos fungicos para confirmacao diagnostica e subsequente extracao de M. canis e as amostras de sangue foram avaliadas por Western blot uni e bidimensional. Para a realizacao dos ensaios de sequenciamento da microbiota, foram colhidas amostras cutaneas, pelos metodos carpete e escova de dentes, de 45 felinos: sintomaticos (n= 15), assintomaticos (n= 15) e negativos (n= 15). Essas amostras foram submetidas ao sequenciamento de alto rendimento na plataforma Illumina utilizando analise dos genes 16S rRNA e ITS1. Na avaliacao bidimensional das proteinas de M. canis, foi observado que elas se encontravam majoritariamente na faixa de pH de 7 a 3. Ainda, o WB revelou um amplo perfil antigenico com proteinas variando de 150 a 20 kDa em peso molecular. As proteinas de 30 e 42 kDa demonstraram intensa imunorreatividade em felinos sintomaticos e assintomaticos e baixa imunorreatividade nos negativos. O teste de Western blot conseguiu discriminar bem os gatos positivos dos gatos negativos para M. canis demonstrando elevados indices de sensibilidade (92,5%) e especificidade (90%) diagnosticas. Quanto aos resultados da analise de sequenciamento, foi observado que gatos sintomaticos e assintomaticos apresentaram um padrao semelhante na composicao e distribuicao da microbiota. Adicionalmente, nao foi observado diferenca estatistica na distribuicao relativa do Microsporum entre esses grupos. Os resultados do imunodiagnostico sugerem que as proteinas de 30 e 42 kDa apresentam elevada acuracia diagnostica e podem ser utilizadas em teste de WB, bem como sao potenciais candidatas a purificacao e subsequente utilizacao em ensaios enzimaticos. Adicionalmente, conclui-se que a atividade proteolitica do M. canis possui maior acao em ph acido. Em relacao aos dados do sequenciamento, conclui-se que o desencadeamento da dermatofitose esta mais relacionado a fatores intrinsecos referentes a imunidade do hospedeiro do que com fatores relacionados ao dermatofito ou com a distribuicao/composicao da microbiota comensal. Adicionalmente, conclui-se que embora o M. canis seja o agente causal e fator determinante para o desencadeamento da dermatofitose, sua acao isolada nao e suficiente para desencadear a enfermidade.

Dermatophytosis is a superficial fungal disease commonly seen in dermatological practice. This mycosis is an important skin disease of cats because it is contagious, infectious and can be transmitted to people. Currently, several diagnostic techniques are available to confirm clinical suspicion, and the fungal culture remains one of the most employed diagnostic tools. However, dermatophytes are slow-growing fungi and it may take several weeks for results. Therefore, the development of new diagnostic tests as immunodiagnostic, as well as microbiota sequencing Technologies can contribute to the proper identification and development of new diagnostic targets. The aim of this study was to identify the immunodominant proteins of Microsporum canis for the serological diagnosis of feline dermatophytosis. Additionally, this study aimed to evaluate the composition and diversity of skin fungal and bacterial communities of cats with dermatophytosis, asymptomatic cats (carriers of M. canis), and healthy cats. For the M. canis protein study, skin and blood samples were collected from 70 cats: symptomatic (n=20), asymptomatic (n=20), negative (n=20) and heterologous negative (n=10 ). Skin samples were submitted to fungal cultures for diagnostic confirmation and subsequent extraction of M. canis, and blood samples were evaluated by Western blot. For the microbiota study, skin samples were collected by combing the coat using a sterile polyester carpet and toothbrush, from 45 cats: symptomatic (n=15), asymptomatic (n=15) and negative (n=15). Samples were submitted to next-generation sequencing on the Illumina platform using 16S rRNA and ITS1 gene analysis. In the two-dimensional evaluation of M. canis proteins, it was observed that they were distributed in the pH range of 7 to 3. Furthermore, the WB revealed a broad antigenic profile with proteins ranging from 150 to 20 kDa. The 30 and 42 kDa proteins showed strong immunoreactivity in symptomatic and asymptomatic samples and low immunoreactivity in negative samples. The Western blot test was able to distinguish positive and negative cats for M. canis, showing high sensitivity (92.5%) and specificity (90%). The microbiota analysis showed that symptomatic and asymptomatic cats presented a similar pattern in the composition and distribution of skin microbiota. Additionally, no statistical difference was observed in the relative distribution of Microsporum between these groups. Immunodiagnostic results suggest that proteins of 30 and 42 kDa present high diagnostic accuracy and can be applied in WB tests, as well as being potential candidates for purification and subsequent application in serological assays. Additionally, it is concluded that the proteolytic activity of M. canis occurred mainly in acidic ph. Regarding the sequencing data, it is concluded that dermatophytosis is more linked to the host's immunity than to factors associated with the dermatophyte or distribution of the commensal microbiota. Additionally, it is concluded that although M. canis is the causative agent and responsible for triggering dermatophytosis, its isolated activity is not sufficient to trigger the disease.

Dermatophytes and other associated fungi in patients attending to some hospitals in Egypt

Dermatophytes are keratinophilic fungi that infect keratinized tissues causing diseases known as dermatophytoses. Dermatophytes are classified in three genera, Epidermophyton, Microsporum, and Trichophyton. This investigation was performed to study the prevalence of dermatomycosis among 640 patients being evaluated at the dermatology clinics at Kasr elainy, El-Husein and Said Galal hospitals in Cairo and Giza between January 2005 and December 2006. The patients were checked for various diseases. Tinea capitis was the most common clinical disease followed by tinea pedis and tinea corporis. Tinea cruris and tinea unguium were the least in occurrence. Tinea versicolor also was detected. The most susceptible persons were children below 10 years followed by those aged 31–40 years. Unicellular yeast was the most common etiological agent and T. tonsuranswas the second most frequent causative agent followed by M. canis..(AU)

Pseudomicetoma dermatofítico em felino SRD: relato de caso

O presente trabalho relata um caso de pseudomicetoma dermatofítico, em um gato SRD, quatro anos. O pseudomicetoma dermatofítico é uma forma de dermatofitose em que fungos dermatofílicos formam hifas no tecido dérmico e subcutâneo. As lesões nodulares formadas em consequência de infecção do tecido profundo por dermatofítos é o sintoma mais comum. O dermatófico mais comumente encontrado em felinos é Microsporum canis. No caso, o paciente apresentava lesões fistulizadas, nodulares, com exposição de tecido subcutâneo em ambos os membros anteriores, exudativo, mucopurulento e grumos. Histológicamente foi caracterizada Dermatite piogranulomatosa severa com agregados de hifas pleomórficas (Pseudomicetoma Dermatofitico). (AU)

This paper reports a case of Dermatophytic Pseudomycetoma, in a cat NRD, four years. Dermatophytic Pseudomycetoma is a form of dermatophytosis where in dermatophytes fungal hyphae formed in the dermal and subcutaneous tissue. The nodular lesions formed as a result of deep tissue infection by dermatophytes is the most common symptom. The dermatophyt most commonly found in cats is Microsporum canis. In case, the patient had fistulizadas, nodular, with subcutaneous tissue exposure in both forelimbs, exudative, mucopurulent and lumpy. Histologically was characterized severe dermatitis pyogranulomatous hyphae with pleomorphic aggregates (Dermatophytic Pseudomycetoma). (AU)

Pseudomicetoma dermatofítico em felino SRD: relato de caso

O presente trabalho relata um caso de pseudomicetoma dermatofítico, em um gato SRD, quatro anos. O pseudomicetoma dermatofítico é uma forma de dermatofitose em que fungos dermatofílicos formam hifas no tecido dérmico e subcutâneo. As lesões nodulares formadas em consequência de infecção do tecido profundo por dermatofítos é o sintoma mais comum. O dermatófico mais comumente encontrado em felinos é Microsporum canis. No caso, o paciente apresentava lesões fistulizadas, nodulares, com exposição de tecido subcutâneo em ambos os membros anteriores, exudativo, mucopurulento e grumos. Histológicamente foi caracterizada Dermatite piogranulomatosa severa com agregados de hifas pleomórficas (Pseudomicetoma Dermatofitico).

This paper reports a case of Dermatophytic Pseudomycetoma, in a cat NRD, four years. Dermatophytic Pseudomycetoma is a form of dermatophytosis where in dermatophytes fungal hyphae formed in the dermal and subcutaneous tissue. The nodular lesions formed as a result of deep tissue infection by dermatophytes is the most common symptom. The dermatophyt most commonly found in cats is Microsporum canis. In case, the patient had fistulizadas, nodular, with subcutaneous tissue exposure in both forelimbs, exudative, mucopurulent and lumpy. Histologically was characterized severe dermatitis pyogranulomatous hyphae with pleomorphic aggregates (Dermatophytic Pseudomycetoma).

COMPARAÇÃO ENTRE CULTIVO E DETECÇÃO MOLECULAR PARA DIAGNÓSTICO DE DERMATÓFITOS DIRETAMENTE DO PELAME DE CÃES E DE GATOS

Os dermatófitos são responsáveis pela doença fúngica mais frequente na clínica médica veterinária de pequenos animais: a dermatofitose. Trata-se de uma zoonose de distribuição mundial, caracterizada pela infecção de estruturas queratinizadas, como pele, cabelos, pelame, unhas e garras. O cultivo micológico é o padrão de referência para o diagnóstico dessa micose, no entanto requer aproximadamente 15 dias para um resultado definitivo. Métodos de diagnóstico moleculares baseados em PCR possuem elevada sensibilidade e especificidade, além de proporcionarem resultados entre um a três dias. O objetivo deste estudo foi realizar a detecção molecular de dermatófitos diretamente de amostras de pelame de cães e de gatos com suspeita de dermatofitose e comparar os resultados obtidos com o método padrão de referência. Foram coletadas 219 amostras de pelame, as quais foram submetidas ao cultivo micológico e à extração de DNA para realização de análise por qPCR. A comparação entre testes mostrou concordância de resultados em 70% das amostras: a qPCR identificou corretamente amostras positivas em cultivo em 34% dos casos, enquanto identificou corretamente amostras negativas em cultivo em 95% dos casos. Além disso, a qPCR foi capaz de detectar dermatófitos em sete amostras negativas em cultivo. A qPCR detectou maior proporção de dermatófitos em amostras de gatos (20%) do que em amostras de cães (13%). Diferentes métodos prévios à extração de DNA (tratamento por congelamento versus sem tratamento) e uso de amostras com diferentes períodos entre coleta e extração de DNA (menor ou igual a um ano versus maior que um ano) foram comparados, observando-se que o uso de amostras frescas associado ao tratamento por congelamento prévio à extração de DNA proporcionou 64% de positividade na qPCR das amostras positivas em cultivo. Ainda, amostras de alta pureza e concentração de DNA apresentaram 82% de positividade na qPCR das amostras positivas em cultivo. A qPCR pode ser utilizada como um teste de triagem inicial prévio ao cultivo micológico. Ainda assim, a técnica molecular desenvolvida deve ser adaptada com a adição de novos métodos juntos à extração a fim de aumentar sua eficácia, podendo se tornar o método de escolha para a detecção de dermatófitos em amostras clínicas no futuro.

Dermatophytes are responsible for the most common fungal disease in small animal veterinary practice: dermatophytosis. It is a worldwide zoonosis characterized by infection of keratinized structures such as skin, hair, fur, nails and claws. Mycological culture is the reference standard for diagnosis of this ringworm, however it requires at least 15 days for a definitive result. PCR-based diagnostic methods are high sensitivity and specificity and provide results within one to three days. The aim of this study was to perform molecular detection of dermatophytes directly from dog and cat fur samples with suspected dermatophytosis and to compare results with reference standard method. A total of 219 fur samples were collected and submitted to mycological culture and DNA extraction for qPCR analysis. Comparison between tests showed results agreement in 70% of samples: qPCR correctly identified positive samples in culture in 34% of cases; while correctly identified negative culture samples in 95% of cases. In addition, qPCR was able to detect dermatophytes in seven negative culture samples. qPCR detected a higher proportion of dermatophytes in cat (20%) than in dog (13%) samples. Different methods prior to DNA extraction (freezing treatment versus untreated) and use of samples with different periods between DNA collection and extraction (less than or equal to one year versus more than one year) were compared: use of fresh samples associated with freezing treatment prior to DNA extraction yielded 64% positivity in qPCR of positive samples in culture. Also, high purity and high amount of DNA samples yielded 82% positivity in qPCR of positive samples in culture. qPCR can be used as initial screening test prior to mycological culture. Nevertheless, this molecular technique developed must be adapted with addition of new methods together with extraction in order to increase its effectiveness and could become the method of choice for dermatophytes detection in clinical samples in future.